feat(windows-drivers): pf-vdisplay STEP 2 — IddCx device skeleton

DriverEntry -> driver_add builds the full IDD_CX_CLIENT_CONFIG (14 IddCx callbacks +
PnP EvtDeviceD0Entry, all stubs with correct PFN signatures) sized via the ported
IDD_STRUCTURE_SIZE! (size.rs), runs IddCxDeviceInitConfig -> WdfDeviceCreate ->
WdfDeviceCreateDeviceInterface(the owned pf-vdisplay GUID, not SudoVDA) ->
IddCxDeviceInitialize. callbacks.rs has all 14 + device_d0_entry; query_target_info
implements HIGH_COLOR_SPACE. edid.rs salvaged verbatim from the oracle. proto gains
interface_guid_fields() (u128 -> Windows GUID fields). Links IddCxStub (the CI gate);
adapter/monitor/swapchain/IDD-push fill the stubs in STEP 3-6.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packaging/windows/drivers/pf-vdisplay/src/callbacks.rs

@@ -0,0 +1,148 @@
+//! The IddCx client-config callbacks + the PnP `EvtDeviceD0Entry`.
+//!
+//! STEP 2: stubs with the correct PFN signatures (so the config wires up + the driver loads); the real
+//! mode/EDID logic (STEP 4), adapter init (STEP 3), and swap-chain handoff (STEP 5) fill them in. Every
+//! callback is `unsafe extern "C"` to match the wdk-sys `PFN_IDD_CX_*` types; with `panic = "abort"`
+//! (workspace profile) a panic across the FFI boundary aborts rather than being UB. `query_target_info`
+//! is implemented now because it gates HDR (`HIGH_COLOR_SPACE`) and the adapter (STEP 3) sets FP16.
+
+use wdk_sys::iddcx;
+use wdk_sys::{call_unsafe_wdf_function_binding, NTSTATUS, WDFDEVICE, WDFREQUEST};
+
+use crate::{STATUS_NOT_IMPLEMENTED, STATUS_SUCCESS};
+
+/// PnP `EvtDeviceD0Entry` (not an IddCx config callback). STEP 3 calls `DeviceContext::init_adapter`
+/// here (adapter creation is deferred to first D0, not driver_add).
+pub unsafe extern "C" fn device_d0_entry(
+    _device: WDFDEVICE,
+    _previous_state: wdk_sys::WDF_POWER_DEVICE_STATE,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// Async completion of `IddCxAdapterInitAsync`. STEP 3: stash the adapter + start the watchdog.
+pub unsafe extern "C" fn adapter_init_finished(
+    _adapter: iddcx::IDDCX_ADAPTER,
+    _p_in: *const iddcx::IDARG_IN_ADAPTER_INIT_FINISHED,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// SDR mode list for an EDID monitor. STEP 4: EDID-serial lookup + count-then-fill `IDDCX_MONITOR_MODE`.
+pub unsafe extern "C" fn parse_monitor_description(
+    _p_in: *const iddcx::IDARG_IN_PARSEMONITORDESCRIPTION,
+    _p_out: *mut iddcx::IDARG_OUT_PARSEMONITORDESCRIPTION,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// HDR (`*2`) mode list — writes `IDDCX_MONITOR_MODE2` (+BitsPerComponent). Mandatory under FP16.
+pub unsafe extern "C" fn parse_monitor_description2(
+    _p_in: *const iddcx::IDARG_IN_PARSEMONITORDESCRIPTION2,
+    _p_out: *mut iddcx::IDARG_OUT_PARSEMONITORDESCRIPTION,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// Only called for EDID-less monitors; ours always carry an EDID, so this stays NOT_IMPLEMENTED.
+pub unsafe extern "C" fn monitor_get_default_modes(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_GETDEFAULTDESCRIPTIONMODES,
+    _p_out: *mut iddcx::IDARG_OUT_GETDEFAULTDESCRIPTIONMODES,
+) -> NTSTATUS {
+    STATUS_NOT_IMPLEMENTED
+}
+
+/// SDR target (scan-out) modes. STEP 4: pointer-match the monitor + fill `IDDCX_TARGET_MODE`.
+pub unsafe extern "C" fn monitor_query_modes(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_QUERYTARGETMODES,
+    _p_out: *mut iddcx::IDARG_OUT_QUERYTARGETMODES,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// HDR (`*2`) target modes — writes `IDDCX_TARGET_MODE2`. Mandatory under FP16.
+pub unsafe extern "C" fn monitor_query_modes2(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_QUERYTARGETMODES2,
+    _p_out: *mut iddcx::IDARG_OUT_QUERYTARGETMODES,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// Diagnostic only — assign drives everything. STEP 4 logs the committed paths.
+pub unsafe extern "C" fn adapter_commit_modes(
+    _adapter: iddcx::IDDCX_ADAPTER,
+    _p_in: *const iddcx::IDARG_IN_COMMITMODES,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// HDR (`*2`) commit over `IDDCX_PATH2`. Mandatory under FP16.
+pub unsafe extern "C" fn adapter_commit_modes2(
+    _adapter: iddcx::IDDCX_ADAPTER,
+    _p_in: *const iddcx::IDARG_IN_COMMITMODES2,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// Report `HIGH_COLOR_SPACE` so the OS enables the HDR10 wide-gamut/PQ target. Mandatory under FP16.
+pub unsafe extern "C" fn query_target_info(
+    _adapter: iddcx::IDDCX_ADAPTER,
+    _p_in: *mut iddcx::IDARG_IN_QUERYTARGET_INFO,
+    p_out: *mut iddcx::IDARG_OUT_QUERYTARGET_INFO,
+) -> NTSTATUS {
+    // SAFETY: p_out is the framework's (uninitialised) out buffer; zero then set the one field we report.
+    unsafe {
+        core::ptr::write(p_out, core::mem::zeroed());
+        (*p_out).TargetCaps = iddcx::IDDCX_TARGET_CAPS::IDDCX_TARGET_CAPS_HIGH_COLOR_SPACE;
+    }
+    STATUS_SUCCESS
+}
+
+/// Accept the OS's default HDR10 static metadata (the host/client own the stream's final metadata).
+/// Mandatory under FP16.
+pub unsafe extern "C" fn set_default_hdr_metadata(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_MONITOR_SET_DEFAULT_HDR_METADATA,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// Accept (do not apply) the gamma ramp — the client display applies its own transform. MANDATORY once
+/// FP16 is set, or the OS rejects the adapter at init ("Failed to get adapter").
+pub unsafe extern "C" fn set_gamma_ramp(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_SET_GAMMARAMP,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// A swap-chain was assigned to the monitor. STEP 5: spawn the `SwapChainProcessor`.
+pub unsafe extern "C" fn assign_swap_chain(
+    _monitor: iddcx::IDDCX_MONITOR,
+    _p_in: *const iddcx::IDARG_IN_SETSWAPCHAIN,
+) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// The monitor went inactive. STEP 5: drop the processor (RAII joins the worker thread).
+pub unsafe extern "C" fn unassign_swap_chain(_monitor: iddcx::IDDCX_MONITOR) -> NTSTATUS {
+    STATUS_SUCCESS
+}
+
+/// The pf-vdisplay-proto control plane. Returns `()` and completes the request itself (matches the C
+/// `EVT_IDD_CX_DEVICE_IO_CONTROL` shape). STEP 4: dispatch the proto IOCTLs; for now just complete.
+pub unsafe extern "C" fn device_io_control(
+    _device: WDFDEVICE,
+    request: WDFREQUEST,
+    _output_len: usize,
+    _input_len: usize,
+    _ioctl_code: u32,
+) {
+    // SAFETY: `request` is the framework-provided WDFREQUEST; completing it hands it back to the OS.
+    unsafe {
+        call_unsafe_wdf_function_binding!(WdfRequestComplete, request, STATUS_SUCCESS);
+    }
+}